Method of producing cellulose derivative crepe yarns



y 1943- J. G. MONALLY ETAL 2,319,077

METHOD OF PRODUCING CELLULOSE DERIVATIVE CREPE YARNS Filed- July 12, 1959 JAMES G. M NALLY DONALD R MOREY INVENTORS Patented May 11, 1943 METHOD OF PRODUCING CELLULOSE DE- RIVATIVE CREPE YARNS James G. McNally and Donald R. Morey, Rochester, N. Y., assignors to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey Application July 12, 1939, Serial No. 284,096

7 Claims.

This invention relates to the production of synthetic yarns and fabrics and more particularly to .the production of lubricated synthetic yarns.

The invention further relates to the production of highly twisted synthetic yarns of both the regenerated cellulose and cellulose derivative type including cellulose organic acid esters, such as cellulose acetate, cellulose acetate propionate, cellulose acetate butyrate, and the like, which are capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect in the fabric when the fabric is boiled off.

This invention has as its principal object to' provide a synthetic crepe yarn capable, when woven into a crepe fabric construction of producing a true crepe efl'ect when the fabric is boiled off. A further object is to provide a cellulose organic acid ester crepe yam which can be successfully employed in producing a degree of pebble in a given crepe fabric construction deflnitely comparable to that obtained by the use of'natural silk. A still further object is to provide a process of producing such products which is simple to operate, economical and feasible from a manufacturing standpoint. Another object is to provide a method of lubricating or pre-treating yarns composed of cellulose organic acid esterssuch as cellulose acetate and similar esters to adapt them for a variety of textile operations, particularly for high twisting to produce a pracperature above the boiling point of the swelling agent in order that it may completely and effectively displace the swelling agent previously deposited in the body of the yarn. In other words, under normal conditions, we preferto employ a mild acting swelling agent'such as water at ordinary room temperature and to employ a hot lubricating oil. However, the broad scope of our invention includes the use of a rather wide variety of swelling agents, many of which may have more drastic action on the cellulose derivative material than just mentioned, and also includes a wide variety of textile lubricants used under varying degrees of temperature.

While our invention is of course in no way dependent upon or in any way limited, by our theoretical views thereof, the following discussion is provided for the better understanding of our invention and to present an explanation for the remarkable results which are thereby obtained.

A convenient classification of the effect of various liquids on cellulose and cellulose esters and ethers is that of interand intra-micellar swell- 2 me, although there is no clear line of demarkation tical crepe yarn. Other objects will appear hereinafter.

ing invention which, in its broader aspects, comprises impregnating a synthetic yarn such, for example, as a yarn composed of a cellulose organic acid ester such as cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, and the like, first with a swelling agent and, second, impregnating the yarn with an appropriate textile lubricant under such conditions that the swelling agent is displaced by the lubricant, and finally giving the yarn the desired or appropriate degree of twist to render it capable, upon weaving into an appropriate crepe fabric construction and scouring to release a portion of the torsional energy stored in the yarn by the twist, of giving a true crepe or pebble effect to the fabric. Preferably, the swelling agent is of the mild acting variety, that is, a swelling agent of the type which is incapable, even at relatively elevated temperatures, of dissolving or gelatinizing the cellulose derivative material of the yarn. Also the lubricant preferably is applied to the yarn at a tembetween the two, since one often leads gradually into the other. The more highly organized, better crystallized portions of the material are called micelles and, in the case of cellulose and fully esterified cellulose esters or ethers, give rise to fairly sharp X-ray diffraction spots. Because of this better organization, the molecular forces require more work for disruption in a micelle than in regions where the arrangement is more amorphous or random. Therefore, when the fiber is penetrated by some foreign substance, for which the ultimate fiber constituents have an adsorptive aifinity, the foreign molecules will find the disorganized matrix the easiest to penetrate and to be adsorbed on. Whether or not the foreign molecules will penetrate and swell or disrupt the micelles depends, not only on the internal micellar forces, butalso on the size of the penetrating molecule, on the attraction between fiber molecule and penetrating molecule, and on the modification of this latter component by the presence of a third type of molecule, as would be the case in our invention where the swelling agent contains a solvent such as alcohol. Furthermore, the temperature at which the penetration of the cellulose derivative material takes place may play an important part for some swelling agents.

We mention the above theoretical aspects of our invention in order to show the various possibilities of action of the treating liquid on the yarn and the diilerent ways in which various swelling agents may difler one from another in their mechanisms of attack on the fibers. It is our belief that the result of the practice of our invention is a distribution of lubricating film over the material phases of the yarn structure which type of lubrication is, to the best of our knowledge and belief, entirely novel and permits in the yarn structure a degree of reversible displacement between component phases of the structure which has been hitherto unattainable. Our yarn treating process may be regarded as similar on a molecular scale to the known method of impregnating fibrous materials such as wood by soaking the wood in water and subsequently immersing the wood in hot oil whereby the water is vaporized and displaced by the oil.

The lubricants used in the step of displacing the water may be animal, vegetable or mineral oils such as sperm, neats-foot, blown neats-foot, olive, kapok, cottonseed and paraflin oils, or various mixtures of these or similar oils, or, in fact, any of the commonly used textile lubricants. In addition, various wetting, emulsifying and other agents may be included with the oils to assist scouring, if desired.

In the following examples and description, we have set forth several of the preferred embodiments of our invention, but they are included merely for purposes of illustration and not as a limitation thereof.

The single figure of the accompanying drawing is a schematic illustration of the essential steps of the process of our invention.

The numeral l designates an appropriate yarn package from which a thread or strand of cellulose acetate filaments of appropriate denier and composition is continuously withdrawn, passing over guide 3 and thence between feed rolls 4 and 5. Upon emerging from the feed rolls, the yarn passes into the aqueous swelling bath 6 contained in trough 'l', the length of travel in the bath being adjusted by means of guide 8 attached to the lower end of standard 9 which is so mounted as to provide for vertical or other adjustment with respect to the trough 1 in a well-known manner.

The yarn passes from the bath 6 between contacting rolls l and l l. Formany applications rolls in and II run at the same speed as rolls 4 and 5, but in certain cases, it is desirable to impart a small stretch to the yarn while it is in bath 6. This is done by increasing the speed of rolls l0 and H with respect to the speed of rolls 4 and 5. Upon emerging from between rolls l0 and II, the yarn passes directly into the hot oil bath l2 contained in receptacle l3, the path of the yarn being determined by its passage through guides I4, l and 16 as shown. Guides l4, l5 and [6 are mounted upon an arm I1 adapted to pivot upon an appropriate bearing Hi, the position of the arm and the depth of the guide l5 in the bath being adjustable by means of fastening member IE! to provide for a predetermined length of travel of the yarn in the bath and for ease of threading. The bath may be heated by steam coils 20 or equivalent heating device.

The treated yarn upon emerging from the guide l6 passes through guide 2| and thence to a conventional type of down-draft twister 22, the spindle 23 of which is adapted to be driven through pulley 24 and a suitable source of power (not shown) at the required speed.

As will be understood from the previous description, the untreated yarn is impregnated by the limited swelling agent contained in the tank I. This will preferably consist simply of water at room temperature, or an aqueous solution containing polyhydric alcohols such as glycerine, or other alcohols such as methyl and ethyl alcohol, or esters such as ethyl acetate, in such amounts that the swelling agent does not gelatinize or dissolve the yarn. If desired, the yarn may be stretched from about 3% to 15% of its original length during impregnation with the mild swelling agent. although this is in no sense essential to the success of the process. The yarn containing the swelling agent is then passed into the hot oil bath I2 which immediately penetrates the swollen yarn material and displaces the swelling agent. The yarn is then ready to receive the high twist which is inserted by means of the down-draft twister.

It is important that the sequence of steps illustrated in the drawing should be maintained, since our invention is based upon the idea of first impregnating the yarn with the swelling agent, then displacing the swelling agent by means of the hot oily liquid, and finally imparting the desired twist to the internally lubn'cated material, In other words, according to our invention, the swelling treatment must come first and must be followed by the hot oil treatment, since proper creping cannot be obtained by merely treating with a swelling agent, or a lubricant, and then twisting.

Our invention will be further understood by reference to the following specific examples of typical creping processes in accordance therewith.

Example 1 Cellulose acetate yarn is continuously treated while being transferred from one package to another, first at room temperature with a water bath, containing .02% Gardinol, and after emerging therefrom, in a bath containing blown olive oil at a temperature of 110 C. The rate of travel of the yarn is 300 feet per minute, the length of travel in the water bath 24 inches and in the hot oil bath 15 inches.

Example 3 denier cellulose acetate propionate yarn is fed into a tank of water containing 1% of sulionated olive oil, at a temperature of 25 C. The length of travel in the solution is approximately 15". The yarn then is passed directly into a tank containing white mineral oil at a temperature of C., and from this tank directly to the spindle of a downdraft twister rotating at 8000 R. P. M., where it is given a twist of 75 turns per inch. Both S and Z twist yarns are prepared, the S twisted yarn being identified by application of a fugitive tint placed in the water solution. The length of path in the hot oil is approximately 12'', and the temperature is maintained to within 2 degrees.

The treated yarn is then woven into a 2 x 2 canton crepe. the warp construction being 135 ends of 100 denier dull acetate yarn, in a 47 inch reed. The crepe filling is woven at 66 picks per inch. This raw cloth is then entered flat into a tank of water at 98 (3., containing 1% of soap, and worked for 10 minutes, at the end of which time it has shrunk to 30" width. It is then dyed in rope form for hours to a soiree green color.

Example 4 150 denier cellulose acetate yarn is fed into a tank of water at a temperature of 30 C. The

length of travel in the solution is approximately 12". The yarn is then passed directly into a tank containing cocoanut oil maintained at a temperature of 104- l;l C. The length of path in the cocoanut oil is approximately 12". From this tank the yarn is passed over guides to the spindle of a downdraft twister rotating at 8000 R. P. M. where it is given 60-65 turns per inch.

'The treated yarn is then woven into a 2 x 2 canton crepe at 56 picks per inch, with a warp of 135 ends of 100 denier dull acetate yarn in a 4'7" reed. The greige goods are boiled off in a tank containing a 1% neutral soap solution, until they have shrunk to about 28", and are then transferred to a dye bath, and are dyed in rope form to a navy blue shade.

Example 5 150 denier cellulose acetate butyrate yarn is fed into a tank containing a 5% aqueous solution of ethyl acetate at 25 C. The draft rolls leading from this tank are run at slightly higher speed than those feeding yarn into the tank so that the yarn is stretched about 7% while in the aqueous bath. The yarn is then passed through a bath of cottonseed oil at a temperature of 100 0., where it is given a twist of 55 turns per inch. The yarn is then woven into a 4 x 4 canton crepe at 54- picks and boiled off in an appropriate scour bath.

Example 6' 100 denier cellulose acetate propionate yarn is passed into a bath of 10% glycerine and 90% water at room temperature, and then is passed into a tank containing olive oil at 90 C. The yarn is then wound up on a spool which is suitable for the shaft of an up-draft twister. This yarn is then twisted on an up-draft twister to 65 turns per inch and is woven into a matelasse fabric.

While we have found it convenient to describe our invention by reference to certain specific cellulose derivatives, it will be understood that the broad scope of our invention includes the treatment of yarns composed of a wide variety of cellulose organic acid esters including cellulose acetate, cellulose propionate, cellulose butyrate, cellulose acetate propionate, cellulose acetate butyrate, and many other similar materials.

Although we have referred in the above examples to certain specific temperatures for the swelling bath and the hot oil treatment bath. it will be evident that the specific temperature employed in any given case will depend, not only upon the specific composition of the respective baths, but also upon the particular yarn material dealt with and various other considerations The length of travel of the yarn in each of the" baths will also be adjusted in accordance, not only with the desired effect of the various baths upon the yarn, but also upon the yarn material itself. This'will also be governed to a considerable extent upon the speed with which the yarn is drawn through the processing steps. In general, we prefer to employ speeds of 5 ft. to 15 ft. per second for cellulose acetate, for example, but higher or lower speeds may be desirable to meet the requirements of certain manufacturing conditions. The matter of speed is not especially critical, so long as it does not exceed a value which precludes proper impregnation of the yarn by the swelling and hot oil baths and is consistent with allowable spindle speeds.

While in the above examples we have referred to certain specific temperatures for the swelling bath and for the oil bath, it is to be understood that these temperatures may vary rather widely, depending upon the nature of the baths, the speed of the yarn therethrough, the nature of the yarn, the ultimate purpose for which the yarn is intended and various other factors. In fact, we prefer to employ the swelling bath at room temperature, i. e., at about 20-30" 6., although the temperature may range upward to 95 C. or more. Likewise, the oil bath temperature may range from -120 0., although it'may vary considerably from these limits to meet certain specific conditions of operation, within the scope of our invention.

The amount of oil taken up by the yarn may also vary within rather wide limits. By this, we mean the amount of oil present in the yarn as it is wound on the take-up package. We prefer to carry out the process in such manner that it will have an. ultimate oil content of about 1% to about 3%, based on the dry weight of the yarn when crepe twisting.

As to the matter of stretch, it is sometimes advantageous to stretch the yarn slightly, say from 3-l5%,.although so far as giving the yarn creping power is concerned, stretching is in no sense necessary to the success of the process.

The particular degree of twist imparted .to the yarn will vary in accordance with the particular purpose for which the yarn is ultimately to be "sad. In general the twist will be of the order of 50-80 turns per inch, but this will depend on the denier of the yarn, the particular fabric construcion in which it is to be used, and various other factors. In any event, the crepe yarn twisted in accordance with out invention, when woven into an appropriate crepe fabric construction, enables the fabric to shrink widthwise and lengthwise to a degree comparable to the best natural silk crepe now on the market. The degree of shrinkage will depend, not only upon the degree of twist imparted to the yarn but also upon the particular mechanical fabric construction in which the yarn is used.

It will also be understood that we are not limited as to the particular type of apparatus em ployed for carrying out our process, since obvious y a wide variety of suitable devices maybe used with equal success.

One point which we again wish to emphasize is he matter of the second step in our creping process. namely, the displacement of the swelling agent by the hot oil. We have found that the 0 1 must enter the yarn material in a heated condition and must actually displace the swelling which are within the knowledge of those skilled in the art.

ing agent from the yarn while the oil still contains an appreciable amount of heat. As indicated above, when a crepe yarn produced in accordance with our invention is woven into any of the conventional crepe fabric constructions and boiled off in an appropriate scour bath, the resulting fabric possesses an excellent pebble. equivalent in all respects to that obtained with the use of natural crepe silk. The particular appearance of the fabric will, of course, depend, not so much upon the nature of the yarn as upon the particular mechanical construction of the fabric itself. Our invention is not primarily conceined with particular fabric constructions, but primarily with the provision of a commercially feasibly cellulose organic derivative high-twisted crepe yarn which is capable of producing in any appropriate construction the true pebble effect which is so highly characteristic of crepe fabrics.

While our invention is primarily concerned with the process of crepe twisting cellulose acetate and other cellulosic yarns, the broad scope of our invention includes the pre-treatment of the yarn, per se. This is, as set forth above, essentially a process of internal lubrication of the yarn by impregnating the yarn with a relatively low boiling swelling agent and then displacing the swelling agent with an oily liquid having a relatively high boiling point and maintained at a temperature at which the swelling agent has a high vapor pressure. This is, so far as we are aware, an entirely new method of yarn lubrication.

The yarn product thus obtained is novel, not only by virtue of the fact that it is an internally lubricated cellulose organic acid ester yarn, but also by virtue of the fact that it is a yarn which, upon appropriate crepe twisting in accordance with our invention, is capable of being converted into a true crepe yarn. Such internally lubricated yarn is also especially well adapted for various types of textile processing including knitting. weaving, spinning and the like.

What we claim is:

l. The continuous process of producing a highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with an aqueous swelling agent, (2) treating the yarn while in a swollen condition and containing an appreciable amount of the swelling agent with a hot textile lubricant and thereupon twisting the yarn to the desired degree while the yarn is in a swollen condition resulting from said treatment.

2. The continuous process of producing highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with water, (2) treating the yarn while in a swollen condition and containing an appreciable amount of water with a hot oil and thereupon twisting .the yarn to the desired degree while the yarn is in a swollen condition resulting from said treatment.

3. The continuous process of producing highly twisted cellulose acetate crepe yarn capable, when woven into a crepe fabric construction, of

producing a true crepe or pebble eiiect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: 1) treating cellulose acetate yarn with water at 15-30 C'., (2) treating the yarn while in a swollen condition and containing an appreciable amount of water with oil maintained at a temperature of about -120 C., and thereupon twisting the yarn to the desired degree while the yarn is in a swollen condition resulting from said treatment.

4. The continuous process of producing a highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble efiect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with a swelling agent, (2) displacing the swelling agent by a high-boiling textile lubricating agent maintained at a temperature at which the swelling agent has a high vapor pressure, (3) and thereupon crepe twisting the yarn while the yarn is in a swollen condition resulting from said treatment.

5. The continuous process of producing a highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect when theaccumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with ethyl acetate, (2) displacing the ethyl acetate by a high-boiling textile lubricating agent maintained at a temperature at which the ethyl acetate has a high vapor pressure, and (3) thereupon crepe twisting the yam while the yarn is in a swollen condition resulting from said treatment.

6. The continuous Process of producing a highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with glycerine, (2) displacing the glycerine by a highboiling textile lubricating agent maintained at a temperature at which the glycerine has a high vapor pressure, and (3) thereupon crepe twisting the yarn while the yarn is in a swollen condition resulting from said treatment.

7. The continuous process of producing a highly twisted cellulose organic acid ester crepe yarn capable, when woven into a crepe fabric construction, of producing a true crepe or pebble effect when the accumulated torsional energy is released, which comprises continuously passing the yarn through the following steps: (1) treating a cellulose organic acid ester yarn with a swelling agent, (2) displacing the swelling agent by a high-boiling textile lubricating agent maintained at a temperature at which the swelling agent has a high vapor pressure, and (3) thereupon crepe twisting the yarn while the yarn is in a swollen condition resulting from said treatment, at least a portion of the twist being insertted in the yarn while immersed in the lubrican JAMES G. McNALLY. DONALD R. MORE'Y. 

